Heathrow said it will be working with Border Force to strengthen contingency plans to minimise impact to customers’ journeys.
"We want to reassure passengers that most journeys will be unaffected," a spokesperson added. "Those arriving on strike days, particularly those not eligible to use eGates, should be prepared to experience longer wait times at immigration."
Meanwhile, Gatwick said despite the walkouts, flights are expected to arrive and depart to and from the airport as normal, with other government staff assigned to operate passport checks at the border.
